Devices for automatically inserting yarn on a cop for winding a package of yarn are already known. In them the part for trapping and inserting yarn generally traps the yarn by taking it at an intermediate point and draws it, bending it into two sections or branches, namely into an upper branch of good yarn for being wound on the cop and a secondary underlying branch of yarn which is not suitable for being wound on the cop.
In fact this secondary branch of yarn is wound together with the abovementioned good main branch and is damaging in that it winds around the main yarn, more particularly around the section thereof which defines the tail or reserve of yarn, tangling it and making the subsequent operation of yarn winding impossible or difficult, also due to the fact that it prevents connection of the yarn reserve to a further yarn package. The damaging secondary branch must therefore be cut before it is drawn by rotation of the cop together with the good yarn to be wound.
In known yarn insertion devices, the problem of cutting the damaging branch of yarn has already been tackled, but has not been solved satisfactorily as the parts used for cutting the yarn have been provided far from the reel so that there was always a certain length of covering yarn which hindered to a certain extent the winding phase and also due to the fact that occurrence of the cutting action was not always ensured therein.
In fact in some known devices the parts for cutting the damaging branch of yarn are actuated by means of systems with a pneumatic or electromagnetic drive, so that a fault in such a drive system may involve failure to cut the damaging branch of yarn with subsequent tangling of the yarn being wound which leads to rejection of the package of yarn.
Moreover, in other known devices, the parts for cutting the yarn are in the form of individual blades whereon the branch of yarn to be scrapped is rested and cut due to slight resting pressure and the considerable sharpness of the cutting blade. These types of cutting devices, although they are simple, inexpensive and do not depend on pneumatic or electromagnetic drive means for their action, have the disadvantage that, the yarn cutting blade being very sharp and easily accessible to staff in charge, the latter risk injury with a certain facility. They therefore represent a hazard for the physical safety of the staff concerned.
The object of the present invention is that of providing a device for insertion of yarn on a yarn-holder cop in automatic winding apparatus, wherein cutting means are provided to act more safely and efficiently than was the case with traditional devices.
Another object of the present invention is that of providing a device for the insertion of yarn on a reel wherein the cutting parts do not represent a risk for the physical safety of staff.
A further object of the present invention is that of providing a device of the type referred above which has a simple structure and low manufacturing cost.